Knitting machine



' July 29, 1952 y P. w. ams-row 2,604,767

KNITTING MACHINE Original Filed Dec. 30, 1948 4 Sheets-Sheet l lINVENTOR. PAUL W. BRIS TOW BY ATTORNEYS.

July 29, 1952 P. w. BRlsTow KNITTING MACHINE 4 Sheets-Sheet 2 Original Filed Dec. 30, 1948 INVENTOR. PAUL W. BR/STOW BY @In l M7 ATTORNEYS.

July 29, 1952 P; w. BRlsTow KNITTING MACHINE Original Filed Dec. 30, 1948 4 Sheets-Sheet 3 492 50e "'z- 476 l g I g 496v 1l er if' -l Li l FIG. 3. Y

INVENTOR.

-PAUL nl. R/srow -By @WMA/ ATTORNEYS.

July 29, 1952 P. W. BRlsTow KNITTING MACHINE 4 Sheets-Sheet 4 Original Filed Dec. 30, 1948 INVENToR. PAUL W BRISTOW /ZMw y n ATTORNEYS.

Patented July 29, `1952 KNITTING MACHINE Paul W. Bristow, Laconia, N. H., assignor to Scott & Williams, Incorporated, a corporation of Massachusetts Original application December 30, 1948, Serial No. 68,114. Divided and this application June 22, 1950, Serial No. 169,741

. 6 Claims.

This invention relates to a knitting machine and has particular reference to a circular knitting machine of the superposed cylinder type.

This application is a division of my application Serial No. 68,114, filed December 30, 1948.

It is the object of the present invention to provide a safety mechanism to disconnect a pressofiv draw thread mechanism when making plain fabric to avoid complete press-offs.

The foregoing and other objects of the invention particularly relating to details of construction and operation will become apparent from the following description read in conjunction with the accompanying drawings in which:

Figure 1 isa vertical axial section through the needle cylinders and the associated wrap yarn presenting mechanism of a knitting machine embodying the principles of the invention;

Figure 2 is a horizontal section showing in particular the safety interlocking devices de# signed to prevent press-off when making plain socks without transfer of needles to the upper cylinder;

Figure 3 is an elevation of the mechanism illustrated in Figure 2; and

Figure 4 is an inside development of various cams for control of rotating parts of the machine, certain of these parts being indicated in construction lines.

The knitting machine embodying the invention indicated above is of the superposed cylinder type comprising a lower cylinder 2 and an upper cylinder 3. Arranged tov Vslide in slots in the lower cylinder are sliders 4 adapted to engage the lower hooks of double hook latch needles 6, thel upper hooks of which are engageable by sliders 8 in the upper cylinder.

The lower sliders 4 are provided with butts at two levels ID and I2. 'I'hev upper sliders 8 are provided with butts at two levels I6 and I8. The cylinders are preferably provided with inserted xed walls to dene the slots for reception of the sliders and these walls 20 in the ,case of the upper cylinder terminate substantially above its lower end so that the lower portionsof the slider slots are bounded not by stationary'walls but by movable walls of two alternative .forms arranged to slide in the wall slots in the upper cylinder. One set of these indicated at 22 carry butts 26 and are provided with outwardly and downwardly sloping lower ends as indicated most clearly at 30 in Figure 4. The other slidable walls indicated at 24 are `provided with butts 28 and have verge bit extensions such as indicated at 32 in Figure 4. The verge bits are located 2 between the positions of needles which, in the formation of broad ribs, are carried by sliders in the upper cylinder.

The cylinders are rotated and reciprocated in unison through the medium of a vertical shaft 34 which through conventional gearing is driven by the lower cylinder and which through gearing indicated at 46 and 42 drives the upper cylinder. The present machine additionally involves the driving of a wrapping assembly, which action is eifected through gears 44 and 46, the former being carried by the shaft 34.

Arranged to coooperate with theneedles are arcuate sinkers 48 which are provided with4 butts 56 arranged to be acted upon by stationary cams 52 supported by a stationary cylinder 54 inside the lower rotating cylinder. VThis stationary cylinder 54 also supports the fabric guiding tube 56 provided with an extension 5l. i f

The rotary support for the wrap yarn carrying means is indicated generally at 58. It is secured to the gear 46 and includes a member provided with an annular groove 60 Yin which groove are received the rounded pivot-forming projection 62 of wrap yarn carriers 64 surrounded by spring bands 66 and B2. Dummy spacers 65 are provided in locations where wrap fingers are entirely missing so as to maintain proper tension conditions of the spring bands. Each of the wrap yarn carriers 64 has an upper eXtension 68 received in a notch 16 in an individual jack 12. These jacks I2 are provided with slots arranged so that they may embrace an annular ring 'I4 carried by the support 58. In order to guide the jacks 'l2 for radial movement and to position them in xed circumferential locations they are received in slots 16 in the support 58. Each of the jacks is provided with a plurality of butts 13. These butts may be selectively broken away so as to provide selection in the operation of the wrap yarn carriers. ,Y

Each of the wrap yarn carriers 64 is provided with a downward extension extendingv through the upper cylinder and guided at its upperrend in a radial slot 86 in the support 58. The lower spring lband 82 serves to urge the .lower ends of the wrap yarn carriers inwardly. Butts 84 are provided on the wrap yarn carriers to provide for the positive inward movements. of their lower ends and for the arrest of the outward movements of their lower ends.

At its lower end each wrap yarn carrier is provided with aradially directed extension 86 which has a downwardly extending branch 8l provided with the yarn guide openings 88. The

downwardly extending branches 81 are provided with smooth lower inner edge portions arranged to cam the wrap yarn downwardly as the wrap yarn finger or carrier is withdrawn inwardly following a wrapping movement. Beyond these openings each carrier is provided with an abutment-engaging extension 90.

The foregoing describes in a general way the stitch forming elements which are present in the machine to which specically the present invention is applied. Other details of general construction and operation may be found by reference to the parent application mentioned above.

Figures 2 and 3 show a safety mechanism which is 'arranged to prevent a press-off when making plain socks without transfer of needles to the upper cylinder as is commonly done when machines which are normally operated to involve transfer of needles are being tested orv fixed.

When this type of operation is desired it is custernary to render the lower transfer bolt cani inactive so that needles are retained in the lower cylinder rather than transferred as would normally be the case. Under these circumstances, if the machine is operated with the usual cam arrangement to produce a press-off draw thread the press-off bolt cam would be rendered oper-ative in the cycle and consequently press-off would occur from all of the needles then in the lower cylinder. The Bowden wire 412 shown in Figure 3 is the wire which renders the press-off bolt cam active. Heretofore, this was connected directly to the plunger or push rod 415 following cams on the main cam drum. In the present machine there is provided a sliding cas-ting 414 on the plunger 416 to which casting the Bowden wire 412 is attached. A strong spring 488 pulls this casting upwardly against a pin 418 passing through the plunger 416, the upper end of the spring b-eing anchored to an `adjustable collar 482 at the top of the plunger. This spring 488 is so strong that unless the casting 4114 is restrained, the casting 'and plunger 416 will normally act as a single connected unit to operate the Bowden wire 412.

The plunger of the lower transfer bolt cam is indicated in Figures 2 and 3 at 483 and this is normally acted upon by a spring backed plunger 484 of a lever "486 which is pivoted on a post 488 and is moved against the action of a spring 504 by a toggle link 480, the upper end of which engages in a socket 492 in the lever 486 while its lower end is pivoted at 494 to a collar 49B clamped on a plunger 498 operated on by cams on the main cam drum. The collar 498 maybe finely adjusted and then clamped in position through the use of a screw 580 which bears on a fixed collar 502 also carried by the plunger V498.

The lever 486 carries an extension 505 provided with a laterally turned end 508. When the toggle 490 is in operative position so that rise of the plunger 498 will swing the lever 486 to introduce the lower transfer cam, the end 508 is swung out of the path of the casting 414 so that when the plunger 415 is raised the Bowden wire 412 will be operated in the usual fashion to put the pressoff bolt cam in operation. As will appear hereafter, under these conditions a press-off draw thread is formed. The spring 48|] is much stronger than the resistance encountered by the Bowden wire y412 and consequently the latter acts as if rigidly connected to the plunger 416.

Qn the other hand, if the toggle 490 is removed from the socket 492 so that the lower transfer cam remains withdrawn despite rise of the the machine during knitting of a sock. After fixing the trouble, the main drum and the chain are both moved to starting position and a new sock is immediately started rather than waste time and yarn in finishing a sock already spoiled. If any butt is behind bolt cam 643', the spring merely yields while a drum cam is passing under theplunger 416.

The operation of the machine to the extent that it is related to theinvention herein claimed may be best described with particular reference to Figure 4 which illustrates the various cams for controlling the rotating instrumentalities. Various of these cams correspond generally in their construction and functions to cams commonly provided in this general type of machine. 485 is the lower transfer bolt cam which has been referred `to as controlled by the plunger 484 in Figures 2 and 3. The press-off bolt cam. is 643. The lower cylinder forward stitch cam 558 is mounted in usual fashion for radial movement and also together with reverse stitch cam 652 and lower cam 655 for axial movement :to control the lengths of stitches drawn by needles operating in the lower cylinder. With thesecams there is associated the center cam 654.

The race 655 is followed by the butts 26 and 28 of the sliding walls 22 and 24. Cam 651 Iacts on the outer edgesof the butts 28 `and 28 to prevent the sliding walls from being pulled out es the sliders are titled during transfer actions.

The operation of the machine so far as it is pertinent .to the invention herein claimed may be best started with consideration of the formation of loopers rounds which constitute the completion of a stocking after the formation of its toe. In .this operation all the needles are carried by lower cylinder sliders and the sliders lare rotating so as to carry the various elements through the cams from the right to the left of Figure 4. The transfer bolt cam 65S and the welt bolt cam 612 are inactive in the upper cylinder cam section causing the sliders in the upper cylinder .to follow a normal knitting race. In the lower cylinder cam section the run down or forward stitch cam 650 is in action and the welt bolt cam 618 is also in action so that all of the needles knit plain stitches in the lower cylinder, drawing yarn from a yarn feed finger in the position 845. It will, of course, be clear that as is conventional this machine is provided with a plurality of yarn feeding fingers acting at a single feed point, which fingers may be selectively brought into and taken out of action to provide desired main yarn changes.'

Following the formation of the loopers rounds transfer of alternate needles to the upper cylinder is accomplished in conventional fashion by the'action on suitable long Iand medium transfer butts of thelower cylinder sliders by the lower transfer cam 485. The division of needles thus provided effects the knitting of 1 x 1 rib fabric.

After the transfer to the 1 x 1 condition of the needles the welt is made for the press-off draw thread locking courses. The upper welt bolt cam '610 is stepped out, :as the long butts are passing, to clear short butts, and as the short butts are passing it is pulled all the way out, leaving the upper cylinder sliders in the welt race at constant level with their knitting butts passing over the top of the stitch cam B60. In the meantime the alternate needles carried by the lower cylinder slides continue to knit plain fabric. After about three and one half such courses of knitting a change is made to produce the loose or pull courses for the press-off draw thread.

To effect this result the upper Welt bolt cam 610 is stepped back into action, first against the short butts as they are passing and then fully inwardly as the long butts pass this cam, to resume 1 X 1 rib knitting on the needles engaged by the upper cylinder sliders. The clearing bolt cam 614 and the press-off bolt cam E43 are now additionally brought into action to act on the lower cylinder sliders. -`Concurrently with the bringing into action of the cam 643 a latch opener and needle leveler blade, not herein shown but shown in said parent application, are moved into action. The latch opening occurs as the needles rise over the bolt cam 618. While the needles carried by both top and bottom cylinder sliders now draw yarn at the main yarn feed the lower cylinder sliders pass down the stitch cam 650 but then rise over the cam B14 and cam 615 to clear their stitches, shedding the stitches as they pass under the press-off bolt cam 643, leaving only the rib needles with loops. A fabric take-up plus a toe pocket weight, not herein shown, elongate the rib loops by pulling the extra length of yarn drawn by the needles controlled by the lower cylinder sliders.

After, for example, three and one half courses of the foregoing the cams 610, 614 and 643 are stepped out and welt knitting is resumed in the fashion previously described. When sulicient welt courses are formed the bolt cam 610 is again stepped into action and the knitting of 1 X l rib' fabric is resumed. Thereafter knitting occurs as described more fully in said parent application.

It will be evident from the foregoing that the use of the devices illustrated particularly in Figures 2 and 3 prevents press-off when making plain socks Without transfer of needles to the upper cylinder, as during testing or fixing.

What is claimed is:

1. A knitting machine comprising superposed needle cylinders, needles carried by said cylinders, a normally inactive cam which, when active, controls needles in one of said cylinders to cause said needles to press-olf stitches, pattern controlled means normally effective to render said cam active, a yielding connection between said cam and said means to prevent said means from rendering said cam active whenever movement of said cam to active position is resisted, a cam for effecting transfer of needles from the cylinder aforementioned to the other cylinder, pattern controlled connections for rendering said transfer cam effective, and means operable upon interruption of the last mentioned connections to restrain movement of the rst mentioned ca to active position.

2. A knitting machine comprising superposed needle cylinders, needles carried by said cylinders, means controlling needles in one of said cylinders to effect press-off of stitches therefrom, mechanism for transferring needles from the rst mentioned cylinder to the other, and means for preventing such press-off in the event that said transfer mechanism is rendered inactive so that al1 needles remain in the first mentioned cylinder.

3. A knitting machine comprising superposed needle cylinders, needles carried by said cylinders, means controlling 'needles in one of said cylinders to eiect press-off of stitches therefrom, said press-off normally occurring from spaced needles in said cylinder, mechanism for transferring needles from the first mentioned cylinder to the other, and means for preventing such press-off in the event that said transfer mechanism is rendered inactive so that all needles remain in the first mentioned cylinder.

4. A knitting machine comprising superposed needle cylinders, needles carried by said cylinders, means controlling needles in one of said cylinders to effect press-off of stitches therefrom, said press-off normally occurring from spaced needles in said cylinder during 1 X l rib knitting, mechanism for transferring needles from the first mentioned cylinder to the other, and means for preventing such press-off in the event that said transfer mechanism is rendered inactive so that all needles remain in the first mentioned cylinder.

5. A knitting machine comprising superposed needle cylinders, needles carried by said cylinders, means controlling needles in one of said cylinders to effect press-off of stitches therefrom, mechanism for transferring needles from the first mentioned cylinder to the other, and means including yieldable connections for preventing such press-off in the event that said transfer mechanism is rendered inactive so that all needles remain in the first mentioned cylinder.

6. A knitting machine comprising superposed needle cylinders, needles carried by said cylinders, a normally inactive cam which, when active, controls needles in one of said cylinders to cause said needles to press-off stitches, pattern controlled means normally effective to render said cam active, a yielding connection between said cam and said means to prevent said means from rendering said cam active whenever movement of said cam to active position is resisted, an element having its position controlled independently of said cam, and means effective when said element is in a predetermined position to resist movement of said cam to active position.

PAUL W. BRISTOW.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,151,662 Kent et al Mar. 21, 1939 2,440,333 Fregeolle Apr. 27, 1948 FOREIGN PATENTS Number Country Date 494,107 Great Britain Oct. 20, 1938 

